Slight weeping is normal on some vehicles. There wasn't a lot of weeping with Chev small blocks, though, for instance. Generally, you're not going to see a catastrophic failure. You'll have leakage and bearing noise, first.

1996 Chevy Lumina with 75K I just replaced the OEM w/p and it was easy, especially for a FWD car. It was sitting on top front of the V6 and you replace the impeller , not the housing, so it is very straight forward. And a Brand New pump from AZ was only 20.00. Now the Thermostat is a whole different story. It is the FWD nightmare you would expect.

On a '94 Saturn SL1, I changed what I'm fairly sure was the original pump at 173,000. The lifetime warranty replacement from Advance lasted 22,000. My '01 Silverado started leaking at around 80,000. My other pumps have lasted somewhere between those two figures. Not that they can't fail immediately, but mine have always started leaking progressively more from the weep hole.

Japanese cars usually get great life out of the pump, but only if you use the non-silicate coolant. My parents learned the hard way that just because Honda and Mitsu coolant is green in color does not mean it is the same green stuff sold in Advance Auto.

Many American cars get good life from their pumps too, they weren't the ones who dyed coolant in such ways. Green was green, orange was orange, up until recently.

There is another factor in water pump life. This destroys many of the more recent ones. Some pumps have a plastic impeller that will have a blade fail. The engine will overheat, but coolant will not leak out of the water pump, causing confusion. VW cars are the worst for this.